Let’s get one thing straight: Australia is weird. And I mean that in the most natural way possible. Australia is so weird because 80% of its species are endemic, meaning that they don’t exist anywhere else in the world. This makes sense when you see that Australia is basically a gigantic island, but it’s still pretty weird. Because of this isolation, endemic Australian animals are bizarre, but also unable to defend themselves against climate change and invasive species. Let’s take a look.
One of the most notorious predators in Australia is the dingo, or a wild dog. It’s considered an apex predator, and was most likely brought to Australia by Asian sea-travellers. There are so many dingoes in mainland Australia that they are seen as a pest (“dingo fences”, made to protect grazing sheep, are fairly common). However, they also help keep the prey population in check, therefore aiding the biodiversity of Australian grasslands.
Dingoes normally feast on small animals, like wombats and wallabies, but will sometimes try and take down Australia’s star, the kangaroo. Because there are so many of both, we’ll focus on them.
Kangaroos are herbivores, so they’re not normally too violent. They’re endemic to Australia, and they’re the best adapted marsupial to grasslands. They have specialised teeth that crop grass, and the back molars grind it down. (These molars eventually wear down and fall out, but more always grown in). Kangaroos are also very good swimmers. (This is the part where it gets interesting) The kangaroo will flee into water if threatened by a predator, say, a dingo. If followed into the water, the kangaroo may attempt to hold the other animal under the water until it drowns. If there isn’t any water around, and the dingo pounces, the kangaroo will grab it by the forepaws and kick forward, disembowelling the animal in the jump.
Weird, right?!
But don’t go thinking that dingoes are wimps – they’re probably the main reason the thylacine went extinct. The thylacine was presumably a major predator of kangaroos, but due to the dingoes tougher bone structure and stronger jaw, the food competition probably got too much so it kicked the bucket. Of course, the dingo wasn’t the only cause for extinction – humans and their nasty hunting habits probably contributed, as well as wide-spread diseases. Either way, when the thylacine disappeared and the dingoes were just starting out, the kangaroo population rose. With the dingo introduction, it went down again. We can see this trend in nearly every predator/prey relationship on earth.
Dingoes normally feast on small animals, like wombats and wallabies, but will sometimes try and take down Australia’s star, the kangaroo. Because there are so many of both, we’ll focus on them.
Kangaroos are herbivores, so they’re not normally too violent. They’re endemic to Australia, and they’re the best adapted marsupial to grasslands. They have specialised teeth that crop grass, and the back molars grind it down. (These molars eventually wear down and fall out, but more always grown in). Kangaroos are also very good swimmers. (This is the part where it gets interesting) The kangaroo will flee into water if threatened by a predator, say, a dingo. If followed into the water, the kangaroo may attempt to hold the other animal under the water until it drowns. If there isn’t any water around, and the dingo pounces, the kangaroo will grab it by the forepaws and kick forward, disembowelling the animal in the jump.
Weird, right?!
But don’t go thinking that dingoes are wimps – they’re probably the main reason the thylacine went extinct. The thylacine was presumably a major predator of kangaroos, but due to the dingoes tougher bone structure and stronger jaw, the food competition probably got too much so it kicked the bucket. Of course, the dingo wasn’t the only cause for extinction – humans and their nasty hunting habits probably contributed, as well as wide-spread diseases. Either way, when the thylacine disappeared and the dingoes were just starting out, the kangaroo population rose. With the dingo introduction, it went down again. We can see this trend in nearly every predator/prey relationship on earth.
Believe it or not, kangaroos get even cooler. Their adaptations are absolutely ridiculous. Antilopine kangaroos, who live in grasslands, have larger nasal passages that allow more heat to escape. There has to be some sort of cooling mechanism when there’s no shade! In general, kangaroo bodies are well adapted to high surface temperatures, unlike their wallaby relatives (many wallaby species are going extinct, due to invasive species and food competition). Kangaroo mothers can put off giving birth in times of drought (this is called diapause), so that the joey will be born at a good time and stands a better chance at surviving into adulthood.
Kangaroos aren’t the only animals with cool adaptations, however. The bridled nail-tail wallaby has a nail at the end of its tail. Scientists aren’t sure why this is, but they do know it’s an adaptation – other wallaby species don’t have this nail. It might aid speed, by helping the wallaby pivot when running. The nail-tail wallaby also has a much stronger immune system than other marsupials, so it is of great interest to scientists.
Another animals with interesting adaptations is the northern hairy-nosed wombat. Aside from it’s hairy nose, they have no tail and an incredibly tough backend, which consists of mostly cartilage. If the wombat is threatened, it will dive into the nearest hole and run, their butts acting as protection. It’s difficult for the predator to grab hold of the wombat after it’s in a hole, because there’s nothing to latch onto.
Kangaroos aren’t the only animals with cool adaptations, however. The bridled nail-tail wallaby has a nail at the end of its tail. Scientists aren’t sure why this is, but they do know it’s an adaptation – other wallaby species don’t have this nail. It might aid speed, by helping the wallaby pivot when running. The nail-tail wallaby also has a much stronger immune system than other marsupials, so it is of great interest to scientists.
Another animals with interesting adaptations is the northern hairy-nosed wombat. Aside from it’s hairy nose, they have no tail and an incredibly tough backend, which consists of mostly cartilage. If the wombat is threatened, it will dive into the nearest hole and run, their butts acting as protection. It’s difficult for the predator to grab hold of the wombat after it’s in a hole, because there’s nothing to latch onto.
However, the hairy-nosed wombat is critically endangered, which is a shame because they’re really cute. They’re dying out mostly because of the small population (there’s about 230 left). The wombats all live very close together, so natural disasters render them very vulnerable. Disease also spreads very fast, and because of their small stature and tendency to stay in holes, they don’t win often in the competition for food. However, conservation efforts by humans are slowly helping the wombats make a comeback.
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But there is still the issue of invasive species. One of the hairy-nosed wombats main predator is the red fox, introduced to Australia in the 1830s. It’s considered an apex predator, and is directly linked to the decline or extinction of many species including the extinction of the desert-rat kangaroo, endangerment of bettongs, and our old friend, the bridled nail-tail wallaby. Red foxes are only in Australia because when the British came over to colonize Australia, they brought their hobbies with them. A popular English sport was fox hunting, but the fox population eventually got out of control. To be fair, fox hunting is still popular – it’s legal all throughout Australia.
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Note: The cane toad is an invasive species. They breed profusely, and they secrete bufotoxin from their skin, a substance poisonous to most Australian native animals - except for the meat ant. When ants attack the toad, it just stands still because it thinks the poison will kill the ants, but it doesn't, so the ants basically eat the toad alive. Take that, invasive species.
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Sources:
National Geographic. Dingo. \ \ 2016. 27 November 2016. <http://www.nationalgeographic.com/animals/mammals/d/dingo/>.
Queensland Government. Bridled nailtail wallaby. 7 May 2013. 25 November 2016. <https://www.ehp.qld.gov.au/wildlife/threatened-species/endangered/endangered-animals/bridled_nailtail_wallaby.html>.
The Nature Conservancy. Australia: How We Work. n.d. 24 November 2016. <http://www.nature.org/ourinitiatives/regions/australia/howwework/index.htm>.
Wikipedia. Bridled nailtail wallaby. 8 November 2016. 25 November 2016. <https://en.wikipedia.org/wiki/Bridled_nail-tail_wallaby>.
—. Brigalow belt. 30 December 2015. 24 November 2016. <https://en.wikipedia.org/wiki/Brigalow_Belt>.
—. Cane toads in Australia. 19 November 2016. 27 November 2016.
<https://en.wikipedia.org/wiki/Cane_toads_in_Australia>.
—. Kangaroo. 25 November 2016. 27 November 2016. <https://en.wikipedia.org/wiki/Kangaroo>.
—. Northern hairy-nosed wombat. 18 November 2016. 24 November 2016. <https://en.wikipedia.org/wiki/Brigalow_Belt>.
—. Red foxes in Australia. 8 November 2016. 27 November 2016. <https://en.wikipedia.org/wiki/Red_foxes_in_Australia>.
—. Thylacine - Extinction in Mainland Australia. 17 November 2016. 27 November 2016. <https://en.wikipedia.org/wiki/Thylacine#Extinction_from_mainland_Australia>.
National Geographic. Dingo. \ \ 2016. 27 November 2016. <http://www.nationalgeographic.com/animals/mammals/d/dingo/>.
Queensland Government. Bridled nailtail wallaby. 7 May 2013. 25 November 2016. <https://www.ehp.qld.gov.au/wildlife/threatened-species/endangered/endangered-animals/bridled_nailtail_wallaby.html>.
The Nature Conservancy. Australia: How We Work. n.d. 24 November 2016. <http://www.nature.org/ourinitiatives/regions/australia/howwework/index.htm>.
Wikipedia. Bridled nailtail wallaby. 8 November 2016. 25 November 2016. <https://en.wikipedia.org/wiki/Bridled_nail-tail_wallaby>.
—. Brigalow belt. 30 December 2015. 24 November 2016. <https://en.wikipedia.org/wiki/Brigalow_Belt>.
—. Cane toads in Australia. 19 November 2016. 27 November 2016.
<https://en.wikipedia.org/wiki/Cane_toads_in_Australia>.
—. Kangaroo. 25 November 2016. 27 November 2016. <https://en.wikipedia.org/wiki/Kangaroo>.
—. Northern hairy-nosed wombat. 18 November 2016. 24 November 2016. <https://en.wikipedia.org/wiki/Brigalow_Belt>.
—. Red foxes in Australia. 8 November 2016. 27 November 2016. <https://en.wikipedia.org/wiki/Red_foxes_in_Australia>.
—. Thylacine - Extinction in Mainland Australia. 17 November 2016. 27 November 2016. <https://en.wikipedia.org/wiki/Thylacine#Extinction_from_mainland_Australia>.